Essentially, they have found that they can manipulate the frequency and wavelength of a photon while it's in storage to use for a kind of "coding system." By manipulating the photon's properties, they can effectively use them for data storage. Before they thought they could only stop the photon and release it; now they can change it.
The paper:
http://www.nature.com/ncomms/2016/160405/ncomms11200/full/ncomms11200.htmlhttp://phys.org/news/2016-04-colour-photons-diamond-quantum-memory.htmlResearchers from the Institute for Quantum Computing at the University of Waterloo and the National Research Council of Canada (NRC) have, for the first time, converted the colour and bandwidth of ultrafast single photons using a room-temperature quantum memory in diamond. Shifting the colour of a photon, or changing its frequency, is necessary to optimally link components in a quantum network. For example, in optical quantum communication, the best transmission through an optical fibre is near infrared, but many of the sensors that measure them work much better for visible light, which is a higher frequency. Being able to shift the colour of the photon between the fibre and the sensor enables higher performance operation, including bigger data rates.
The research, published in Nature Communications, demonstrated small frequency shifts that are useful for a communication protocol known as wavelength division multiplexing. This is used today when a sender needs to transmit large amounts of information through a transmission so the signal is broken into smaller packets of slightly different frequencies and sent through together. The information is then organized at the other end based on those frequencies. In the experiments conducted at NRC, the researchers demonstrated the conversion of both the frequency and bandwidth of single photons using a room-temperature diamond quantum memory.
